How Is a Clinical Trial Planned and Carried Out?
In order to make a decision about whether to participate in a clinical trial, it helps to understand more about how trials are conceived and run. You will also want to know what happens when a trial is over.
Where do the ideas for trials come from?
The ideas for clinical trials often originate in the laboratory. Researchers develop a clinical trial protocol (the plan for a trial) after laboratory studies indicate the promise of a new drug or procedure. The first trials of a particular drug or procedure are focused on safety (phase I), and later trials focus on whether the drug or procedure is effective (phase II or phase III).
What is a protocol?
Every trial has a person in charge, usually a doctor, who is called the protocol chair or principal investigator. Phase I and phase II studies generally refer to the person in charge as the principal investigator. Phase III studies generally have a protocol chair, under whose direction multiple principal investigators carry out the protocol in participating sites. The protocol chair or principal investigator prepares a plan for the study, called a protocol. The protocol explains what the study will do, how it will be carried out, and why each part of the study is necessary. For example, the protocol includes:
The reason for doing the study
How many people will be in the study
Who is eligible to participate in the study
What study drugs participants will take, if any
What medical tests they will have, if any, and how often
What information will be gathered
Every doctor or research center that takes part in the trial uses the same protocol. This ensures that patients are treated identically no matter where or if they are receiving treatment, and that information from all the participating centers (if there is more than one) can be combined and compared.